Exhaust system



Feb. 24, 1959 F. l.. SIMMONDS 2,874,627

EXHAUST SYSTEM v Filed Sept. 5. 1954 United States Patent EXHAUST SYSTEMFrancis L. Simmonds, De Kalb, Ill. Application September 3, 1954, SerialNo. 454,153 7 Claims. (Cl. 98115)l The present invention relates to anovel exhaust system and more particularly, to a novel system forexhausting grease-laden or otherwise contaminated air from rooms such askitchens.

As is well known, the air in kitchens often becomes contaminated withgrease and smoke and the like and unless some provision is made forexhausting the air from the kitchen, the contaminating material in theair collects on the kitchen walls and ceiling. While this problem ispresent in domestic kitchens, it is particularly acute in commercialkitchens wherein large amounts of fried foods are prepared. In order toexhaust such contaminated air from kitchens, it has heretofore been thegeneral practice to mount an exhaust fan in a wall opening and blow theair directly to the exterior of the building and in some installations,a large canopy has been positioned over the cooking stove and over theexhaust fan toV restrain smoke and grease-laden air rising from thestove from circulating throughout the entire kitchen. However, suchprior installations have ynot been entirely satisfactory since the airblown directly through the wall opening often contacts the exteriorsurface of the building so that grease and the like are deposited on theexterior surface. In addition, grease and the like collects rapidlyonthe interior surfaces of the canopies used in heretofore knowninstallations so that frequent cleaning is necessary.

In prior installations using canopies, it has often been necessary tooperate the exhaust fan at a high speed in order to prevent contaminatedair from escaping from under the canopy and depositingcontaminatedmaterial such as grease and the like on the exterior surfaceof the canopy or the walls of the kitchen. However, when the exhaust fanis operated at a high speed, an undesirable draft may be createdthroughout the entire kitchen or even throughout the entire building,which draft may interfere with the proper operation of otherair-treating apparatus in the building. For example, it has been foundthat if a furnace is located in the building, the draft created by theexhaust fan may set up a reverse draft in the chimney of the furnace andthereby prevent proper operation o f the furnace. Also the draftset upby the exhaust fait may interfere with the proper'operation of anair-conditioning equipment within the'building.

It isapriinary object of the`present linvention `to provide ariovelsystem for exhausting airfrom kitchens and the like to the,exterior of aibuilding,`which system is constructed Vso as to Vpreventany contaminating materials in '-the air'fro'rnbeing deposited ontheexterior surface of the building.

Another object ofthe Vlinreseritiinvention is to provide anoyel4 systemfor exhausting contaminated air from a kitchen "or the like'to theexterior of the building wherein 'substantial portions of thecontaminated materials ar'e re- Ymovedlfrom the airbefore the airisdischarged f rom thc Vsystem whereby to reduce any possibility of thecontami- Ynating'materials being deposited onn the surface of thebuilding. 1 i Y {Another important object kof the present invention isto 2,874,627 Patented Feb. 2,4, 195,9

ICC,

.provide a novel air exhaust system including an exhaust fan and acanopy, which system is constructed soas to reduce substantially therate at which contaminating materials are deposited on the interiorsurfaces of the canopy.

A further object of the present invention is to provide a novel systemof the above described type which is of simple and economicalconstruction and which may be readily disassembled for cleaning purposesand the like.

A further object of the present invention is to provide a novel airexhaust system wherein an exhaust fan may be operated at high speeds forpreventing contaminated air from circulating from a stove or the likethroughout the kitchen or room without creating an undesirable draftthat will interfere withthe proper operation of other ap-v paratus suchas a furnace or air conditioning equipment that may he located withinthe building.

Other objects and advantages of the present invention will becomeapparent from the following description and the accompanying drawingswherein:

Fig. l is a vertical sectional view of an exhaust system embodying theprinciples of this invention;

Fig. 2 is an enlarged cross sectional view taken along line 2--2 in Fig.l;

Fig. 3 is a cross sectional view taken along line 3-3 in Fig. l;

Fig. 4 is a fragmentary perspective view illustrating portions of thenovel system `in position to be assembled together; and

Fig. 5 is a cross sectional view of a slightly modified discharge endsection of the exhaust system of this invention. i

Referring now more specifically to the drawings wherein like parts aredesignated by the same numerals throughout the various figures, anexhaust system 10 embodying the principles of the present invention isshown in Fig. l

and includes a large canopy 12 made of sheet metal or wall 26 to theexterior of the building. Preferably, a sheet metal panel 21 having alower trough portion 23 is mounted on the wall 26 behind the stove forcollecting any grease or the like which may splatter from the stove.

The canopy 12 which is preferably made of sheet metal may be of anyknown construction and may be mounted to the Wall 26 by a suitable knownmeans such as bolts or screws, not shown, and, therefore, the canopyneed not be further described in detail. In the past, it has been thepractice to mount the exhaust fan within the wall opening but thisarrangement has permitted the contaminated air drawn beneath thecanopy'to swirl around and come into intimate contact with the interiorsurface of the canopy whereby air contaminating materials such as greaseand smoke are deposited on the canopy at a rapid rate. In accordancewith the present invention, the rate at which the contaminatingmaterials are deposited on the interior Vof the canopy 12 issubstantially reduced by forming the duct means 14 so that it includes atube 28 whichv extends from the wall 26 welltoward the centralportion ofthecanopy. The tube 28 is provided with an annular ilange 30 forabutting against the wall 26 and is secured to the wall by means of aplurality of screwsr32 extending through the flange and into the wall.The exhaust fan 16 is mounted within the tube 28 by any suitable meanssuch as a plurality of brackets 34 and it should be noted that the fanis spaced well within the inlet end of the tube. Wththis arrangement thetube 28, which has a diameter substantially less than the crosssectional dimensions of the canopy, provides for a Venturi-like actionadjacent the mid-portion of the canopy whereby the velocity of the airmoving through the canopy is rapidly increased as the air moves towardand into the tube. It has been found that this action substantiallyreduces swirling of the air within and against the interior surfaces ofthe canopy and the wall 26 and the larger portion of the air tiows inthe manner indicated by the arrows so as to reduce the rate at whichcontaminating material such as grease and smoke are deposited on thecanopy or the wall 26.

The fan 16 may be of any known variable speed type and need not bedescribed in detail. However, suitable switch means, not shown, shouldbe provided for controlling the operation and speed of the fan as will be understood. The electric motor of the fan is preferably air cooled andin order to prevent contamination of the fan motor,V a cooling air inlettube 36 is provided which extends from the motor through a suitableopening in the duct means 14 and through the wall 26 to the exterior ofthe building. A cooling air outlet tube 38 is provided which extendsfrom the fan motor housing through the duct means 14 and to any desiredpoint outside of the canopy 12.

The duct means 14 also includes a sheet material liner 40 extendingthrough the wall 26 and in order to prevent deposits of grease and thelike from building up on the exterior surface of the wall 26, the ductmeans 18 is mounted in communication with the liner 40. It should benoted that the liner 40 extends into the duct means 18 as at 43 in orderto insure against the escape of contaminated air between the inlet endof the duct means 18 and the wall 26. The duct means 18 includes anelbow 42 made of sheet metal or any other suitable material, which elbowhas its inlet end secured against the wall 26 and its outlet enddirected downwardly along the wall. The inlet end of the elbow isprovided with a flange 44 through which a plurality of screws 46 and thelike are passed for securing the elbow to the wall. It should be notedthat the cross sectional dimensions of the elbow 18 are considerablylarger than the diameter of the inlet tube-28 and the liner 40 so thatthe air passing into the elbow may expand and undesirable back pressureis avoided. This arrangement permits more efcient operation of theexhaust fan than heretofore known installations which include gravitybiased shutters at the discharge side of the wall opening, whichshutters must be forced open by the air whereby they create considerableback pressure which reduces the efficiency of the fan. The duct means 18also includes one or more sections 48 and 50 depending from the lowerend of the elbow. The section 48 is detachably connected to the elbow bymeans of a plurality of hook members 52 which are adapted to engage overstuds 54. The section 50 is similarly attached to the lower end of thesection 40 by hook members 56 and studs 58. It will be appreciated thatany other desired means may be provided for detachably connecting thevarious sections of the duct means 18 together. The

lowermost section of the ductmeans 18, which in the embodiment shown isthe section 50, has its bottom end closed by a receptacle 60 made ofsheet metal or any other desired material, which receptacle is alsodetachably connected to the section by means of hook members 62 andstuds 64 or any other desired means.

In addition, the lowermost section or the section 50 is provided withlateral air outlet openings 66, 68 and 70, which openings are preferablycovered with metal screen or hardware cloth panels 72, 74 and 76. Itshould be noted that the rear wall 78 of the section 50, or in otherwords, the wall adjacent the wall 2,6 of the building is imperforate.Therefore, the air discharged from the section 50 is not directed towardthe building or the wall 26. In addition, outwardly flared bafflemembers 80 and 82 extrend from the rear wall 78 of thersection 50 fordirecting the discharged air away from the buildllg- With thisstructure, the exhausted air is prevented from contacting the exteriorsurface of the building wall whereby to pre# vent deposits of grease andthe like from accumulating on the building wall.

In order to further reduce any possibility of contaminating material inthe air from contacting the exterior surface of the building wall, meansis provided in the duct means 18 for removing substantial portions ofthe contaminating material from the air before the air is ultimatelydischarged. This means includes a plurality of sheet metal baffles 86removably fixed within the elbow section 42 on brackets or the like 88.These baffles are directed downwardly across the path of the airentering the elbow in the manner shown so that the air is brought intointimate contact with the baffles. As the air contacts the baies 86,grease and the like condenses from the air and is deposited on thebaffles. As the grease builds up on the baffles, it drains therefrom anddrops into the container 60 at the lower end of the duct means. Itshould also'be noted that the lower ends of the elbow section 42, thesection 48 and the section 50 are respectively provided with inwardlydirected funnel portions 90, 92 and 94, which funnel portions extendinto the next lower section and thereby prevent any grease or the likefrom escaping between the junctions of sections. The funnel portionsalso serve to direct any grease or the like running down the walls ofthe various sections toward the interior of the duct means so thatgrease dropping from the funnel portions falls directly into thereceptacle 60. It has been found that the bafe members 86 and the funnelportions -of duct means 18 are effective for removing 'enough grease orother contaminating materials from the air for most installations.However, for some installations wherein the air is unusually heavilycontaminated, it has been found desirable to provide filter units overthe discharge openings in the section 50. Thus, as shown in Fig. 5,filter units 96 which may be made of any suitable material such asfiberglass or the like are placed over the discharge openings and may beretained in position by suitable bracket means 98 or the like.

As mentioned above, the exhaust fan should be operated at a speedsufficient to prevent any contaminated air from escaping around thecanopy 12 and in installations heretofore in use, this has sometimescreated an undesirable draft which interferes with the operation offurnaces or air conditioners. In accordance with the present invention,the possibility of the creation of such an undesirable draft has beeneliminated by providing an air inlet duct 100 extending from the outsideof the building through the wall 26 adjacent the lioor of the kitchenand beneath the fan. The passage of air through the inlet duct 100 maybe controlled by gravity biased shutters 102 or suitable means, notshown, may be provided for positively positioning the shutters in thedesired manner for controlling the How of air. Preferably, a screen 104is provided across the inlet end of the duct 100 to prevent insects orrodents from gaining access to the kitchen. With the duct 100 and theshutters 102, it will be appreciated that the circulation of air throughthe exhaust system of this invention will be from the duct 100 past thestove and then into the canopy whereby undesirable drafts in theremaining portions of the kitchen or throughout the building areeliminated.

From the above. description, it is seen that the present invention hasprovided a novel exhaust system which is fully capable of accomplishingthe objects heretofore set forth. More specifically, it is seen that thepresent inventiony has provided an exhaust system wherein the air isdirected in a manner so as to reduce the rate of coutamination of thecanopygand also to eliminate contamination of the exterior surface ofthe building. Further more, it is, seen that withfthe novel exhaustsystem of the present invention, the exhaust fan may be operated moreeiciently and at a higher speed so as to prevent contaminated .air fromescaping around. the canopy' With- '5 out creating undesirable draftsthroughout the building. While for the purpose of illustrating thepresent invention only, one exhaust fan and its associated duct meanshas been illustrated, it will be appreciated that in many commercialkitchens, a number of stoves and long canopies are provided so that aplurality of exhaust fans and associated duct means should be used. Ithas been found that for optimum results, one exhaust fan and itsassociated duct means should be placed at eight or nine foot intervalsalong the canopy in commercial installations.

While the preferred embodiment of the present invention has been shownand described herein, it is obvious that many structural details may bechanged without departing from the spirit and scope of the appendedclaims.

The invention is claimed as follows:

l. A system for exhausting contaminated air from a room or the likecomprising duct means extending from a point within a room through awall to the exterior of the room, fan means disposed within the ductmeans for moving air from the room through the duct means, additionalduct means communicating with thev outlet end of said rst mentioned ductmeans and disposed for extending downwardly therefrom adjacent anexterior surface of said wall, receptacle means connected with andsubstantially closing a lower end portion of said last mentioned ductmeans for receiving contaminating material from the air being exhausted,said last mentioned duct means having lateral air outlet meansV adjacentto and above said receptacle means, and bae means associated with saidlast mentioned duct means for directing air emerging from said outletmeans in a predetermined manner away from said wall.

2. An exhaust system, as defined in claim 1, which includes canopy meansdisposed over at least a part of said iirst mentioned duct means, andwherein said irst mentioned duct means has an inlet end disposed wellwithin said canopy means and substantially spaced from interior surfacesof said canopy means whereby to direct air being exhausted in a mannerto reduce contact with said canopy means.

3. An exhaust system, as defined in claim l, which includes generallydownwardly extending baille means in said second mentioned duct meansdisposed for intimate contact for aii being exhausted and having lowerend means spaced from interior surfaces of said second mentioned ductmeans and in generally vertical alignment with said receptacle means forremoving contaminating material from the air and directing contaminatingmaterial so that it will drop into said receptacle means. f

4. An exhaust system, as dened in claim 1, whic includes air inlet meansextending from the exterior of the room and opening `into the roomsubstantially beneath and aligned with said rst mentioned duct means sothat air entering through said inlet means may be means in order toeliminate the application of the suction to the room or other portionsof the building of which the room is a part.

5. A system for exhausting contaminated air to the exterior of abuilding comprising duct means for extending between the interior andthe exterior of the building, fan means for moving air through said ductmeans, additional duct means mountable in communication with said rstmentioned duct means for extending downwardly and along the exterior ofthe wall of a building, said last mentioned duct means including aplurality of sections, quick release means detachably connecting saidsections, the lowermost of said sections having a closed bottomproviding a receptacle, certain of said sections including an inwardlyextending lower end portion projecting int-o an adjacent lower sectionand providing bafe means for directing air contaminating material towardsaid receptacle, the air-contaminating material thereby being kept awayfrom the walls of said additional duct means, said last mentioned ductmeans having lateral air outlet opening means adjacent a lower endthereof and above said receptacle, and means associated with the lowerend of said last mentioned duct means for directing air emerging fromsaid outlet opening means away from the exterior wall of the building.

6. An exhaust system, as defined in claim 5, wherein said secondmentioned duct means has an imperforate portion adjacent the exteriorwall of the building, said air outlet opening means being disposed inother portions of said second mentioned duct means, and wherein saidmeans for directing air emerging from said outlet opening means awayfrom the exterior Wall of the building includes bafe members extendingfrom opposite sides of said imperforate duct means portion.

7. An exhaust system, as deiined in claim 6, which includes filter meansdisposed across said air outlet opening means.

References Cited in the le of this patent UNITED STATES PATENTS 640,484Nelson Jan. 2, 1900 1,553,973 Ballon Sept. 15, 1925 1,568,532 RiesnerJan. 5, 1926 1,710,586 McCrory Apr. 23, 1929 1,885,016 Ryan Oct. 25,1932 2,034,995 Sibley 5.---- Mar. 24, 1936 2,226,641 Sonntag Dec. 31,1940 2,392,038 Gaylord Jan. 1, 1946 2,393,957 Baumgartner Feb. 5, 1946V2,539,344 Garraway Jan. 23, 1951 FOREIGN PATENTS 591,169 GreatBritaini-- Aug. 8, 1947

